Week 6 Physicalism
Physicalism: Nothing over and above physical stuff
Supervenience
作业 Detailed Summary of Searle's Mind: A Brief Introduction, pp. 41-49, 52-61
These pages from Searle's book focus on the philosophical concept of materialism and its various forms in the context of the mind-body problem.
Troubles with Dualism:
Searle begins by highlighting the shortcomings of Cartesian dualism, which posits two distinct realms of reality: the mental and the physical. This dualism faces the seemingly intractable problem of explaining how these two realms interact causally. How can mental events like decisions cause physical events like raising an arm, and vice versa? Searle argues that Descartes never adequately addressed this problem, and subsequent attempts to reconcile dualism with modern physics appear ad hoc and unconvincing.
The Turn to Materialism:
Due to the difficulties with dualism, many philosophers have turned to materialism, the view that the only reality is material or physical reality. Consequently, mental states, if they are real, must be reducible to or ultimately nothing but physical states.
Searle then outlines the historical development of different materialist approaches to the mind:
Behaviorism:
- Methodological behaviorism: This approach, influential in psychology, focused on studying only observable behavior and correlating stimuli with responses. While not explicitly denying the existence of mental states, it considered them scientifically irrelevant.
- Logical behaviorism: This philosophical movement claimed that statements about mental states could be translated into statements about actual and possible behavior. However, this faced difficulties in providing non-circular translations and accounting for the causal relations between mental states and behavior.
Physicalism and the Identity Theory:
With the decline of behaviorism, physicalism emerged, claiming that mental states are identical with brain states. This identity theory faced several objections:
- Leibniz's Law: Critics argued that mental and brain states have different properties, violating the principle that identical things must share all properties. Identity theorists countered that this was due to our current ignorance about the brain.
- Common-sense objection: The identity theory seemed to require two sets of properties (mental and physical) to identify mental states with brain states, seemingly falling back into a form of dualism. Identity theorists responded by proposing a "topic-neutral vocabulary" to describe mental states, but Searle finds this answer unsatisfactory.
- Neuronal chauvinism: Critics pointed out that the identity theory seemed to limit mental states to beings with brains, excluding the possibility of mental states in other physical systems or machines. This led to a shift from type-type identity theory (every type of mental state is identical with a specific type of brain state) to token-token identity theory (each individual instance of a mental state is identical with some instance of a physical state).
Functionalism:
To address the limitations of the identity theory, functionalism emerged, defining mental states by their causal relations and functions within the organism. This approach emphasizes that mental states are characterized by their roles in mediating between stimuli, other mental states, and behavior, regardless of their specific physical realization. While functionalism offered advantages over behaviorism and type-type identity theory, it still faced the challenge of explaining the nature of the inner mental states that perform these functions.
Computer Functionalism (Strong AI):
This view, highly influential in cognitive science, posits that the brain is a digital computer and the mind is a computer program. This offered a seemingly clear solution to the mind-body problem by drawing an analogy between the mind-program and the brain-hardware. However, Searle argues against this view in the next chapter, using his famous Chinese Room argument.
Other Versions of Materialism:
Searle briefly mentions two other materialist positions:
- Eliminative materialism: This view argues that mental states do not exist at all and that our common-sense "folk psychology" will be replaced by a mature neuroscience that explains behavior without positing mental entities. Searle criticizes this view for mischaracterizing folk psychology and its propositions.
- Anomalous monism: This position, defended by Donald Davidson, argues that mental events are physical events but that there are no strict psychophysical laws connecting them. Searle does not discuss this view in detail in these pages.
Searle concludes this section by expressing his dissatisfaction with all of these materialist theories, arguing that they fail to capture essential features of the mind, particularly consciousness and intentionality. He believes that these theories are driven by a desire to eliminate the subjective and non-physical aspects of mental phenomena, which ultimately leads to an inaccurate and incomplete picture of the mind.
This summary provides a detailed overview of Searle's critical analysis of various materialist approaches to the mind-body problem. He argues that these approaches, while attempting to offer a solution to the difficulties of dualism, ultimately fall short by neglecting or denying the essential features of consciousness and intentionality.
Ideal physics
- Why not mental studies
- No supervenient entity, which is meant ot be fundamental
- Fundamental entities cannot be dependent on something else, which is the definition of being fundamental
Which suffice to conclude that Mind studies a fundamental study, is not supervenient on physical studies at all.
Over questioning over how to characterize physical entities
Initial answer with divide-into-atom theory. (There always being smaller particles) #todo
Explanation
Identity
Everything trivially depends on itself
The kinds of things that we regard identical: something happening is an event
Event identity thesis
Features
Fiber firing:
Subjective pain, physical pain, people sitting besides(circumstance)
Identity of Events and Physical Events:
Identity of Events:
The question of event identity asks whether two seemingly different descriptions actually refer to the same event. For example, is "Brutus stabbing Caesar" the same event as "Brutus killing Caesar"? What about "the assassination in the Roman Senate on the Ides of March"?
There are two main approaches to this issue:
- Metaphysical approach: This view treats event identity as a metaphysical question requiring specific criteria to determine when two descriptions refer to the same event. Different philosophers have proposed various criteria, leading to a spectrum of positions:
- Unifiers: They argue for coarse-grained event identity, where seemingly different descriptions often refer to the same event.
- Multipliers: They advocate for fine-grained event identity, where even slight differences in description result in distinct events.
- Moderate views: These positions fall somewhere between the two extremes, often employing criteria like causal extensionality (Davidson), mereological inclusion, or spatiotemporal location to determine event identity.
- Semantic approach: This view emphasizes the role of language and argues that event identity is primarily a semantic question about the referents of our event-describing expressions. The meaning and reference of these expressions depend heavily on context and linguistic conventions, making the question of "real" event identity undecidable from a purely metaphysical perspective.
Physical Events:
- Change: Some argue that all physical events must involve change, while others contend that static events (e.g., an object resting) can also be considered physical events.
- Intentionality: The distinction between intentional actions and unintentional bodily movements raises questions about whether both should be categorized as physical events. Some argue for a distinction based on the involvement of mental states, while others see it as a purely descriptive difference.
Property
Properties/Features
- General
- Features determine what exists
Example: hysteria We want to identify things that we perceive to exist (Physically or Neuraly)
Non-physical pain : phantom pain
MR
- Brains(wetware)
- beliefs
- pains
- Computer(silicon)
- Alien
- Animal
Over brain and neurons, if we have some structures arranged in certain way like neuron to constitute thought, etc.
Julius: mind=operational
Only need to care over how these neurons organize, behave, interact. Looking over what the neurons do
Questions:
If identity is dependent over physicalism, why bother ask in this complex way rather than saying Everything is physical
Behaviorism
All behaviors, including those associated with mental states, are acquired through conditioning processes, such as classical and operant conditioning.
Identifying the relationships between environmental stimuli (inputs) and behavioral responses (outputs), aiming to formulate laws that govern these connections.
All we need for describing mind is laws: How I react to certain inputs
- Inputs
- Outputs
Noam Chomsky - Wikipedia Chomsky strongly oppose to this theory.
Functionalism
c focuses exclusively on observable behaviors, while functionalism allows for internal mental states.
For example, a functionalist might analyze the mental state of "belief" as a state that is caused by certain types of evidence and that leads to certain types of actions. This analysis doesn't specify the exact physical or neurological realization of the belief state, only its functional role within the cognitive system.
Functionalism can be seen as a more nuanced and flexible version of behaviorism. It retains the focus on causal relations and functions but allows for a richer account of mental states by including internal, non-behavioral components.
Behaviorism vs. Functionalism: "The mind is like a Coke Machine"
| S1 | S2 | |
|---|---|---|
| $50 | nothing -> S2 | Coke -> S1 |
| $1 | Coke -> S1 | Coke -> S2 |
Behaviorism: How this Automata is organized in the Input-Output way.
Functionalism: Machine's internal states. How these machine states are inter-connected in internal ways. Lawful transitions within these internal states.
Epiphenomenalism(副现象主义)
Epiphenomenalism is the view that mental events are caused by physical events in the brain, but have no causal effects on physical events. In other words, mental events are seen as causally inert by-products of physical processes. According to epiphenomenalism, while it may seem like our thoughts and feelings influence our actions, this is merely an illusion. The physical chain of events in the brain is sufficient to produce our behavior, and our conscious experiences play no causal role. This view raises questions about the purpose and significance of consciousness, as it suggests that our mental lives are essentially passive and have no real impact on the world around us.
The Coke Machine Example and Functionalism
The coke machine example is a thought experiment used to illustrate the concept of functionalism in the philosophy of mind. Functionalism argues that mental states are defined by their functional roles, meaning their causal relations to sensory inputs, other mental states, and behavioral outputs.
Here's how the coke machine example demonstrates this:
Imagine two different coke machines:
- Machine 1: This machine has a simple design. When you insert $1, it dispenses a Coke.
- Machine 2: This machine has a more complex design with multiple internal states. When you insert $1, it goes through several internal transitions before dispensing a Coke.
Behaviorism vs. Functionalism:
- Behaviorism: From a behaviorist perspective, both machines are identical in their relevant functions. They both take $1 as input and produce a Coke as output. The internal mechanisms are considered irrelevant.
- Functionalism: Functionalism, however, distinguishes between the two machines based on their internal states and transitions. While both machines ultimately produce the same output, the internal processes leading to that output are different. Machine 2 has a more complex functional organization with distinct internal states that play specific causal roles in the overall process.
Relevance to the Mind-Body Problem:
The coke machine example highlights how functionalism can be applied to the mind-body problem. Just like the coke machines, two individuals might exhibit the same behavior (e.g., raising their arm) but have different internal mental states (e.g., one might be doing it intentionally, while the other might be responding to a reflex). Functionalism allows us to account for these differences in mental states by focusing on their distinct functional roles and causal relations within the cognitive system, regardless of the specific physical realization (e.g., neurons firing) of those states.
In summary, the coke machine example demonstrates that functionalism goes beyond behaviorism by considering not just the input-output relations but also the internal functional organization of a system. This allows for a more nuanced and detailed account of mental states and their causal roles in producing behavior.
It's important to note that the coke machine example is a simplified illustration and doesn't capture the full complexity of the mind-body problem. However, it serves as a useful starting point for understanding the core idea of functionalism and how it attempts to explain the relationship between mental states and physical processes.
Trivial mind and body as certain connections
How the zombie argument undermines physicalism
- Attack supervenience: World is not a physical one because the consciousness could be independently absent without any change in physical world (human vs. Zombie).
- Attack physicalism's explanatory power: If zombies could exist, then physical facts cannot explain all the facts (i.e., not able to explain the differences between human and zombie).